The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 11, 2011
Filed:
Mar. 14, 2008
Tadaaki Oikawa, Kai, JP;
Hiroyuki Uwazumi, Minami-Alps, JP;
Tadaaki Oikawa, Kai, JP;
Hiroyuki Uwazumi, Minami-Alps, JP;
Fuji Electric Co., Ltd., , JP;
Abstract
A perpendicular magnetic recording medium is disclosed in which a soft magnetic layer used as a low Klayer can be stably produced with high performance. Thermal stabilization of magnetization, ease of writing by a magnetic head, and SNR also are improved. A method of manufacturing the medium is disclosed. The perpendicular magnetic recording medium includes at least a nonmagnetic underlayer, a magnetic recording layer, and a protective layer formed in this order on a nonmagnetic substrate. The magnetic recording layer includes a low Klayer having a relatively small perpendicular magnetic anisotropy constant (Kvalue), and a high Klayer in which the Kvalue is relatively large, and the low Klayer includes a soft magnetic thin film including an iron group element-based microcrystal structure, in which a nitrogen element is added to a ferromagnetic material mainly containing one of metals of Co, Ni and Fe or an alloy of the metal. The thin film has a crystal structure of a face-centered cubic lattice or hexagonal close packed, and a preferred crystal orientation plane parallel to a plane of the film is a (111) plane in the face-centered cubic lattice structure, and a (002) plane in the hexagonal close packed structure.